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Renée L. Eriksen, Caleb Knepper, Michael D. Cahn and Beiquan Mou

After a preliminary screening of over 3500 cultivars, we selected 200 butterhead, cos, crisphead, leaf, and stem lettuce (Lactuca sativa L.) and wild prickly lettuce (Lactuca serriola L.) varieties to test under high water (150% evapotranspiration [ET]) and low water (50% ET) conditions in the field, and tracked commercially relevant traits related to growth and marketability, maturity, and physiology. Plants typically reduced growth and appeared to reallocate developmental resources to achieve maturity quickly, as indicated by traits such as increased core length. This strategy may allow them to complete their life cycle before severe drought stress proves lethal. Although most cultivars experienced a reduction in growth under low water conditions relative to high water conditions, some cultivars had a significantly reduced yield penalty under stress conditions. Among the different types of lettuce, the fresh weight (FW) of cos cultivars was most affected by drought stress, and the FW of leaf lettuce was least affected. Cos cultivars tended to bolt early. Crisphead cultivars Cal-West 80, Heatmaster, and Marion produced large heads and did not bolt under low water treatments, and butterhead cultivars Buttercrunch and Bibb also produced relatively large heads with very little bolting and no signs of tipburn. The four green leaf cultivars Slobolt, Grand Rapids, Western Green, and Australian showed no statistically significant difference in FW among high and low water treatments in multiple trials, and may be good choices for growers who wish to minimize losses under reduced irrigation. The identification of potentially drought-tolerant varieties and the information from this study may be helpful for cultivar selection by growers under drought conditions, but this study also serves as a step forward in the genetic improvement of lettuce to drought stress.

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Bernardo Ordás, Rosa A. Malvar, Amando Ordás and Pedro Revilla

. Summarizing, reciprocal effects in sugary × sugary enhancer hybrids have been only reported for sugar content in the kernel and not for agronomic traits; furthermore, the effects on the sugar content are found to be contradictory in the very limited number of

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Reid R. Rice and William F. Tracy

corn deficient in a number of agronomic traits. The selection limitations arising from the importance of table quality are compounded by the narrow genetic diversity within sweet corn germplasm as several bottlenecks occurred over the course of sweet

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Mercè Rovira, Juan Francisco Hermoso and Agustí J. Romero

). Agronomic characteristics. The following measurements were evaluated annually over a 9-year period (2003–11): the number of suckers (basal shoots), trunk cross-sectional area [TCSA (square centimeters)] measured at 20 cm above ground level, tree height

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Antonios Petridis, Ioannis Therios and Georgios Samouris

relies on some agronomical factors, one of which is the cultivar. Because phenolic compounds play an important role in olive fruit and virgin olive oil quality and present several health benefits, the aim of the present study was to determine the phenolic

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Philip J. White, John E. Bradshaw, M. Finlay, B. Dale, Gavin Ramsay, John P. Hammond and Martin R. Broadley

crops through application of mineral fertilizers, combined with breeding varieties with an increased ability to acquire mineral elements, is advocated as an immediate agronomic strategy both to increase mineral concentrations in edible produce and to

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Zhongshuai Gai, Yu Wang, Jutang Jiang, Hui Xie, Zhaotang Ding, Shibo Ding and Hui Wang

resource nursery at Qingdao Agricultural University, had good agronomic characteristics. To further identify and evaluate the quality of these two tea germplasms for tea breeding, we measured the biochemical components of young shoots in spring and analyzed

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Laura P. Peña-Yam, Liliana S. Muñoz-Ramírez, Susana A. Avilés-Viñas, Adriana Canto-Flick, Jacobo Pérez-Pastrana, Adolfo Guzmán-Antonio, Nancy Santana-Buzzy, Erick A. Aguilera-Cauich and Javier O. Mijangos-Cortés

Capsicum chinense Jacq. An experimental design involving completely randomized blocks with four repetitions was used. Agronomic management was conducted in the following manner: the transplant was performed in growbags (Pelemix, Guadalajara Jalisco, Mexico

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Edward J. Boza, Juan Carlos Motamayor, Freddy M. Amores, Sergio Cedeño-Amador, Cecile L. Tondo, Donald S. Livingstone III, Raymond J. Schnell and Osman A. Gutiérrez

Ecuadorian Amazon. H. Castro, a graduate in Agronomy from the Inter-American Institute for Cooperation on Agriculture (IICA, Turrialba, Costa Rica), was a cacao expert who did most of his research at his own farm called “Theobroma.” The earliest report of

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Bruce W. Wood

chelated Fe can trigger Ni deficiency. This antagonistic effect of Fe and DPTA on Ni nutritional physiology is important to the production of certain horticultural and agronomic crops and therefore merits consideration in development of mineral nutrient